1. Field of the Invention
The present invention relates to ultralight airfoils, rotating along their own axis, for generating energy.
2. Background Information
Kites, or semi-rigid wings, can be defined as aerodynamic structures which, to keep their shape during their use, need tie-rods (similar for example to those on a suspended bridge). Kites or semi-rigid wings have been used so far essentially for sports objectives, so as to exploit only a small part of the potential of these new aerodynamic structures.
In the first steps in the history of flight, it was frequent to see the use of aerodynamic structures reinforced by the use of tie-rods.
The improvement of material characteristics and the increases in speed in time have removed the use of such technology.
The use of tie-rods for reinforcing structures which are not rigid enough appears again with the Francis Rogallo wing in 1948 and with the following development of kites and ultra-light planes.
However, strangely, the use of tie-rods, usually applied for lightening and making it possible to build, for example, big sized bridges, has never been extended to the manufacturing of propellers, when from the propulsion type they were transformed into wind energy catching propellers.
The continuing use of traditional propellers in the aeolian sector in practice has prevented the development of aeolian generation techniques at a height, being that the propellers weight is an almost impossible constraint to overcome, as the prior arrangements demonstrate since they can operate only when there are very strong winds.